/Engine/Source/Runtime/CoreUObject/Public/UObject/UObjectBaseUtility.h
Returns the licensee version of the linker for this object.
the licensee version of the engine's package file when this object was last saved, or GPackageFileLicenseeVersion (current version) if this object does not have a linker, which indicates that a) this object is a native only class, or b) this object's linker has been detached, in which case it is already fully loaded
int32 GetLinkerLicenseeUEVersion() const